Endoscopic surgery can be used to access the abdominal cavity via natural openings (mouth, anus, vagina, urethra) of the body and through the peritoneal lining of the abdominal cavity. Obviously, the size and shape of instruments that may be passed through a bodily lumen in order to perform a medical procedure in the abdominal cavity are greatly restricted due to the anatomical properties of the lumen. General surgeons, gastroenterologists, and other medical specialists, routinely use flexible endoscopes for intraluminal (within the lumen of the alimentary canal) examination and treatment of the upper gastrointestinal (GI) tract, via the mouth, and the lower GI tract, via the anus. In these procedures, the physician pushes the flexible endoscope into the lumen, periodically pausing to articulate the distal end of the endoscope using external control knobs, to redirect the distal tip of the endoscope. In this way, the physician may navigate the crooked passageway of the upper GI past the pharynx, through the esophagus and gastro esophageal junction, and into the stomach. The physician must take great care not to injure the delicate mucosal lining of the lumen, which generally may stretch open to a diameter in the range of about 15-25 mm, but normally has a non-circular cross sectional configuration when relaxed.
During such translumenal procedures, a puncture must be formed in the stomach wall or in the gastrointestinal tract to access the peritoneal cavity. One device often used to form such a puncture is a needle knife which is inserted through the working channel of the endoscope, and which utilizes energy to penetrate through the tissue. A guidewire is then fed through the endoscope and is passed through the puncture in the stomach wall and into the peritoneal cavity. The needle knife is removed, leaving the guidewire as a placeholder. A balloon catheter is then passed over the guidewire and through the working channel of the endoscope to position the balloon within the opening in the stomach wall. The balloon can then be inflated to increase the size of the opening, thereby enabling the endoscope to push against the rear of the balloon and to be fed through the opening and into the peritoneal cavity. Once the endoscope is positioned within the peritoneal cavity, numerous procedures can be performed through the working channel of the endoscope.
While current methods and devices used to penetrate tissue are effective, one drawback is that several exchanges and steps are required to form the opening. The small size of the opening formed can also create high resistance to advancing or retracting the endoscope, which is significantly larger than the opening. In the event the endoscope is retracted through the opening, it can also be difficult to locate the opening and re-insert the endoscope. Continued advancement and retraction of the endoscope can also be uncomfortable for the patient. Another drawback of current methods is that a non-sterile passageway is created from the stomach into the abdominal cavity, as the devices carry bacteria from the body lumen into the abdominal cavity.
Accordingly, there remains a need for improved endoscopic translumenal methods and devices.